Physical Review Research最新文献

{"title":"Hydrodynamic hovering of swimming bacteria above surfaces","authors":"Pyae Hein Htet, Debasish Das, Eric Lauga","doi":"10.1103/physrevresearch.6.l032070","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.l032070","url":null,"abstract":"Flagellated bacteria are hydrodynamically attracted to rigid walls, yet past work shows a “hovering” state where they swim stably at a finite height above surfaces. We use numerics and theory to reveal the physical origin of hovering. Simulations first show that hovering requires an elongated cell body and results from a tilt away from the wall. Theoretical models then identify two essential asymmetries: the response of width-asymmetric cells to active flows created by length-asymmetric cells. A minimal model reconciles near- and far-field hydrodynamics, capturing all key features of hovering.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"194 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iterative site percolation on triangular lattice","authors":"Ming Li, Youjin Deng","doi":"10.1103/physrevresearch.6.033318","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033318","url":null,"abstract":"The site percolation on the triangular lattice stands out as one of the few exactly solved statistical systems. By initially configuring critical percolation clusters of this model and randomly reassigning the color of each percolation cluster, we obtain coarse-grained configurations by merging adjacent clusters that share the same color. It is shown that the process can be infinitely iterated in the infinite-lattice limit, leading to an iterative site percolation model. We conjecture from the self-matching argument that percolation clusters remain fractal for any finite generation, which can even take any positive real number by a generalized process. Extensive simulations are performed, and, from the generation-dependent fractal dimension, a continuous family of previously unknown universalities is revealed.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Explosive percolation in finite dimensions","authors":"Ming Li, Junfeng Wang, Youjin Deng","doi":"10.1103/physrevresearch.6.033319","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033319","url":null,"abstract":"Explosive percolation (EP) has received significant research attention due to its rich and anomalous phenomena near criticality. In our recent study [<span>Phys. Rev. Lett.</span> <b>130</b>, 147101 (2023)], we demonstrated that the correct critical behaviors of EP in infinite dimensions (complete graph) can be accurately extracted using the event-based method, with finite-size scaling behaviors still described by the standard finite-size scaling theory. We perform an extensive simulation of EPs on hypercubic lattices ranging from dimensions <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>d</mi><mo>=</mo><mn>2</mn></mrow></math> to 6, and find that the critical behaviors consistently obey the standard finite-size scaling theory. Consequently, we obtain a high-precision determination of the percolation thresholds and critical exponents, revealing that EPs governed by the product and sum rules belong to different universality classes. Remarkably, despite the mean of the dynamic pseudocritical point <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi mathvariant=\"script\">T</mi><mi>L</mi></msub></math> deviating from the infinite-lattice criticality by a distance determined by the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>d</mi></math>-dependent correlation-length exponent, <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi mathvariant=\"script\">T</mi><mi>L</mi></msub></math> follows a normal (Gaussian) distribution across all dimensions, with a standard deviation proportional to <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>1</mn><mo>/</mo><msqrt><mi>V</mi></msqrt></mrow></math>, where <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>V</mi></math> denotes the system volume. A theoretical argument associated with the central-limit theorem is further proposed to understand the probability distribution of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi mathvariant=\"script\">T</mi><mi>L</mi></msub></math>. These findings offer a comprehensive understanding of critical behaviors in EPs across various dimensions, revealing a different dimension-dependence compared to standard bond percolation.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nontrivial fusion of Majorana zero modes in interacting quantum-dot arrays","authors":"Bradraj Pandey, Satoshi Okamoto, Elbio Dagotto","doi":"10.1103/physrevresearch.6.033314","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033314","url":null,"abstract":"Motivated by recent experimental reports of Majorana zero modes (MZMs) in quantum-dot systems at the “sweet spot,” where the electronic hopping <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>t</mi><mi>h</mi></msub></math> is equal to the superconducting coupling <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi mathvariant=\"normal\">Δ</mi></math>, we study the time-dependent spectroscopy corresponding to the <i>nontrivial</i> fusion of MZMs. The term “nontrivial” refers to the fusion of Majoranas from different original pairs of MZMs, each with well-defined parities. We employ an experimentally accessible time-dependent real-space local density-of-states (LDOS) method to investigate the nontrivial MZM fusion outcomes in canonical chains and in a Y-shaped array of interacting electrons. In the case of quantum-dot chains where two pairs of MZMs are initially disconnected, after fusion we find equal-height peaks in the electron and hole components of the LDOS, signaling nontrivial fusion into both the vacuum <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>I</mi></math> and fermion <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi mathvariant=\"normal\">Ψ</mi></math> channels with equal weight. For <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>π</mi></math>-junction quantum-dot chains, where the superconducting phase has opposite signs on the left and right portions of the chain, after the nontrivial fusion we observed the formation of an exotic two-site MZM near the center of the chain, coexisting with another single-site MZM. Furthermore, we also studied the fusion of three MZMs in the Y-shaped geometry. In this case, after the fusion we observed the novel formation of another exotic multisite MZM, with properties depending on the connection and geometry of the central region of the Y-shaped quantum-dot array.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Signatures of the attractive interaction in spin spectra of one-dimensional cuprate chains","authors":"Zecheng Shen, Jiarui Liu, Hao-Xin Wang, Yao Wang","doi":"10.1103/physrevresearch.6.l032068","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.l032068","url":null,"abstract":"Identifying the minimal model for cuprates is crucial for explaining the high-<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi>c</mi></msub></math> pairing mechanism. Recent photoemission experiments have suggested a significant near-neighbor attractive interaction <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>V</mi></math> in cuprate chains, favoring pairing instability. To determine its strength, we systematically investigate the dynamical spin structure factors <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>S</mi><mo>(</mo><mi>q</mi><mo>,</mo><mi>ω</mi><mo>)</mo></mrow></math> using the density matrix renormalization group. Our analysis quantitatively reveals a notable softening in the two-spinon continuum, particularly evident in the intense spectrum at large momentum. This softening is primarily driven by the renormalization of the superexchange interaction, as determined by a comparison with the slave-boson theory. We also demonstrate the feasibility of detecting this spectral shift in thin-film samples using resonant inelastic x-ray scattering. Therefore, this provides a distinctive fingerprint for the attractive interaction, motivating future experiments to unveil essential ingredients in cuprates.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements of extended magnetic fields in laser-solid interaction","authors":"J. Griff-McMahon, S. Malko, V. Valenzuela-Villaseca, C. A. Walsh, G. Fiksel, M. J. Rosenberg, D. B. Schaeffer, W. Fox","doi":"10.1103/physrevresearch.6.033312","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033312","url":null,"abstract":"Magnetic fields generated from a laser-foil interaction are measured with high fidelity using a proton radiography scheme with <i>in situ</i> x-ray fiducials. In contrast to prior findings under similar experimental conditions, this technique reveals the self-generated, Biermann-battery fields extend beyond the edge of the expanding plasma plume to a radius of over 3.5 mm by <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>t</mi></math>=<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mo>+</mo><mn>1.4</mn></math> ns. An analysis of two monoenergetic proton populations confirms that proton deflection is dominated by magnetic fields far from the interaction (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mo>&gt;</mo><mn>2</mn></mrow></math> mm) and electric fields are insignificant. The results are not captured in state-of-the-art magnetohydrodynamics simulations and suggest the need to consider additional physics mechanisms for the magnetic field generation and transport in laser-solid interactions.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"194 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of estimation limits for quantum two-parameter estimation","authors":"Simon K. Yung, Lorcán O. Conlon, Jie Zhao, Ping Koy Lam, Syed M. Assad","doi":"10.1103/physrevresearch.6.033315","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033315","url":null,"abstract":"Measurement estimation bounds for local quantum multiparameter estimation, which provide lower bounds on possible measurement uncertainties, have so far been formulated in two ways: by extending the classical Cramér-Rao bound (e.g., the quantum Cramér-Rao bound and the Nagaoka Cramér-Rao bound) and by incorporating the parameter estimation framework with the uncertainty principle, as in the Lu-Wang uncertainty relation. In this work, we present a general framework that allows a direct comparison between these different types of estimation limits. Specifically, we compare the attainability of the Nagaoka Cramér-Rao bound and the Lu-Wang uncertainty relation, using analytical and numerical techniques. We show that these two limits can provide different information about the physically attainable precision. We present an example where both limits provide the same attainable precision and an example where the Lu-Wang uncertainty relation is not attainable even for pure states. We further demonstrate that the unattainability in the latter case arises because the figure of merit underpinning the Lu-Wang uncertainty relation (the difference between the quantum and classical Fisher information matrices) does not necessarily agree with the conventionally used figure of merit (mean-squared error). The results offer insights into the general attainability and applicability of the Lu-Wang uncertainty relation. Furthermore, our proposed framework for comparing bounds of different types may prove useful in other settings.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emergence of subharmonics in a microwave driven dissipative Rydberg gas","authors":"Zong-Kai Liu, Kong-Hao Sun, Albert Cabot, Federico Carollo, Jun Zhang, Zheng-Yuan Zhang, Li-Hua Zhang, Bang Liu, Tian-Yu Han, Qing Li, Yu Ma, Han-Chao Chen, Igor Lesanovsky, Dong-Sheng Ding, Bao-Sen Shi","doi":"10.1103/physrevresearch.6.l032069","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.l032069","url":null,"abstract":"Quantum many-body systems near phase transitions respond collectively to externally applied perturbations. We explore this phenomenon in a laser-driven dissipative Rydberg gas that is tuned to a bistable regime. Here two metastable phases coexist, which feature a low and high density of Rydberg atoms, respectively. The ensuing collective dynamics, which we monitor <i>in situ</i>, is characterized by stochastic collective jumps between these two macroscopically distinct many-body phases. We show that the statistics of these jumps can be controlled using a dual-tone microwave field. In particular, we find that the distribution of jump times develops peaks corresponding to subharmonics of the relative microwave detuning. Our study demonstrates the control of collective statistical properties of dissipative quantum many-body systems without the necessity of fine-tuning or of ultracold temperatures. Such robust many-body phenomena may find technological applications in sensing.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum routing with teleportation","authors":"Dhruv Devulapalli, Eddie Schoute, Aniruddha Bapat, Andrew M. Childs, Alexey V. Gorshkov","doi":"10.1103/physrevresearch.6.033313","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033313","url":null,"abstract":"We study the problem of implementing arbitrary permutations of qubits under interaction constraints in quantum systems that allow for arbitrarily fast local operations and classical communication (LOCC). In particular, we show examples of speedups over swap-based and more general unitary routing methods by distributing entanglement and using LOCC to perform quantum teleportation. We further describe an example of an interaction graph for which teleportation gives a logarithmic speedup in the worst-case routing time over swap-based routing. We also study limits on the speedup afforded by quantum teleportation—showing an <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>O</mi><mo>(</mo><msqrt><mrow><mi>N</mi><mo form=\"prefix\">log</mo><mi>N</mi></mrow></msqrt><mo>)</mo></mrow></math> upper bound on the separation in routing time for any interaction graph—and give tighter bounds for some common classes of graphs.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong dipole-dipole interactions via enhanced light-matter coupling in composite nanofiber waveguides","authors":"Kritika Jain, Lewis Ruks, Fam le Kien, Thomas Busch","doi":"10.1103/physrevresearch.6.033311","DOIUrl":"https://doi.org/10.1103/physrevresearch.6.033311","url":null,"abstract":"We study the interaction of emitters with a composite waveguide formed from two parallel optical nanofibers in regimes of experimental importance for atomic gases or solid-state emitters. Using the exact dyadic Green's function we comprehensively investigate the coupling efficiency and the fiber-induced Lamb shift accounting for variations in emitter positions and fiber configurations. This reveals coupling efficiencies and Purcell factors that are enhanced considerably beyond those using a single fiber waveguide, and robustness in the figures of merit. We finally investigate resonant dipole-dipole interactions and the generation of entanglement between two emitters mediated through the composite waveguide under excitation. We show that the concurrence can be enhanced for two fiber systems, such that entanglement may be present even in cases where it is zero for a single fiber. All-fiber systems are simple in construction and benefit from a wealth of existing telecommunications technologies, while enjoying strong couplings to emitters and offering interesting light-matter functionalities specific to slot waveguides.","PeriodicalId":20546,"journal":{"name":"Physical Review Research","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142248812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}